The neuropsychological (NP) sequelae of HIV infection include impairment in attention/speed of information processing, executive skills, learning, and perceptual-motor functioning, abilities which are necessary for competent automobile driving. The degree to which individual NP impairments predict unsafe driving is unclear, however, and determining fitness to drive is difficult, since physicians frequently have inadequate data and on-the-road assessments usually do not allow evaluation under emergency conditions. This project aims to develop driving simulations that are sensitive to impaired driving abilities and can be administered on an affordable, PC-based system. We will design two simulations: one will assess routine driving and accident avoidance, and the other will consist of a novel, "virtual city", in which the patient is to plan and execute a drive through neighborhoods to a target location. Using HIV- infected subjects, we will assess the reliability of these assessments and validate the measures by comparing simulator performance (1) in subjects with and without recent automobile accidents and (2) with on-the-road testing. Since driving skills may be affected by commonly-prescribed medications, alcohol and other recreational drugs, and central nervous system disorders of many etiologies, it is anticipated that this technology will have broad applicability for neurobehavioral research and driver assessments. PROPOSED COMMERCIAL APPLICATION: Low cost driving simulator technology has never been systematically validated. The simulator proposed here will be validated and used to collect normative data that can be applied to all areas that require a safe. real world driving environment. Potential markets include assessment of impaired drivers. driver training and rehabilitation (alcohol, drugs, head injuries, disabilities, strokes, etc.), and driver education.